Field of the Invention
The present invention relates to a display that switches an image to be displayed.
Description of the Related Art
Recently, the MR (Mixed Reality) technique has received attention as a technique of seamlessly combining physical and virtual worlds in real time. The MR system sometimes uses a head-mounted display and, for example, a video see-through HMD (Head Mounted Display) is used. In an MR system using the video see-through HMD, a video almost coincident with an object viewed from the pupil position of the HMD user is captured by a camera or the like. The HMD user can view an image (to be referred to as an “MR image” hereinafter) obtained by superimposing CG (Computer Graphics) on this captured image.
If a transmission error of an image frame occurs in the MR system, the field of view of the HMD user may not be ensured or the HMD user may feel unnatural. To solve this, Japanese Patent Laid-Open No. 2008-300983 discloses a technique of, when a transmission error of an image frame occurs, switching an image to be displayed on the HMD from an MR image to a captured image. Japanese Patent Laid-Open No. 2008-306602 discloses a technique of, when a transmission error occurs in image data for the right or left eye, generating an interpolated image using either one of an immediately preceding image and an image on an error-free side based on the motion amount of the HMD user, and displaying the interpolated image on the HMD.
When wireless communication is used to transmit image data, the communication environment sometimes becomes unstable owing to a change of the peripheral environment or the like, and a transmission error intermittently and frequently occurs for a long period. To solve this, in a technique as disclosed in Japanese Patent Laid-Open Nos. 2008-300983 and 2008-306602, when a transmission error frequently occurs, the HMD display image is frequently switched between a normal MR image and another image (captured image or interpolated image). If the HMD display image is frequently switched for each image frame, the HMD user feels unnatural or uncomfortable, and the eyes of the HMD user are strained. This problem is not limited to the HMD, and can arise in all displays of the MR system.
The present invention has been made to solve the above problem, and provides a technique capable of performing switching of the image display suited to viewing in accordance with the state of the communication quality.